Tech Tips: Understanding Power Usage Effectiveness - PUE
June 27, 2011
In today's data center industry, higher operating and energy costs are driving the industry to target new levels of true energy efficiency. One such method of measuring that efficiency, Power Usage Effectiveness (PUE), gives data center managers a better picture of IT power usage versus total power consumption. Once captured and analyzed, understanding your PUE can lead to:
- Reduced power consumption & energy costs
- Maximized IT load
- Minimized infrastructure, cooling & overhead costs
- Improved data center efficiency
With the preferred method of measuring PUE in terms of source energy consumption (kWh), we also understand that there are multiple locations at which to measure IT load power consumption, including the output of UPS, output of a floor-level PDU and at the input of servers or output of a rack-mounted PDU.
Because dedicated data centers and mixed-use data centers have slightly different measurement points, all energy required to operate the data center must be included in the PUE calculation, such as cooling, lighting and all support structure (fire, security and BMS systems). Furthermore, if another power source other than electricity is being used, that amount should be sub-metered and converted into the same units for total energy calculation.This white paper from the Green Grid explains in detail.
If we look even closer, PUE measurement breaks down to four main categories, illustrated here:
While each category of measurement provides a different level of accuracy and need for monitoring devices, the highest level can only be achieved with server level metering capabilities. Furthermore, CPI even offers a PUE Calculator to help you tabulate power usage effectiveness - depending upon the amount of source data you're able to provide, our calculator will provide PUE across multiple categories.
At CPI, we're committed to improving energy efficiency and providing our customers with the latest innovations in power management. That's why we offer rack-mounted PDUs that provide outlet level monitoring and control - giving you the best overall solution for accurate PUE measurement.
Likewise, other CPI products that can also reduce overall energy consumption, improve efficiency and ultimately lower your PUE include the Vertical Exhaust Duct for cabinets utilizing CPI Passive Cooling® Solutions, our Remote Infrastructure Management (RIM-600) device for accurate temperature and humidity monitoring, CPI's Scalable Enterprise Management Application (SEMA) Software and of course, our intelligent PDUs, giving you on-site or remote-based power management down to the device level.